Had you already told your employer about your pregnancy in writing?
Have they given you a letter about your redundancy?

These sites may help...
if you believe they are making you redundant because you are pg you should call the eoc
I suspect they may have to pay you maternity pay plus your redundancy - not sure, sorry
http://www.eoc.org.uk/EOCeng/dynpages/Pregnancy_Maternity3.asp

http://www.dti.gov.uk/er/redundancy/faq.htm

Flexible Jobs

Try as hard as you can to stay employed until 15 weeks before the expected date of birth to get your maternity pay - if you aren't entitled to enough notice to take you to this date, sk them nicely and they may let you be employed until this date as they will get most of the maternity pay back from the government. If they don't, then prolong the consultation period by putting up suggestions for avoiding redundancy or appeal against the decision to make you redundant.

I was made redundant whilst on maternity leave. Basically, if it's only you, you may have a case - if there are others, and you are being treated in the same way, you just have to take what's offered!! Good luck on both the job and pregnancy front!!